On 18 Nov 2021, at 7:35, Eric Timmons wrote:

> On 11/18/21 3:45 AM, Marco Antoniotti wrote:
>> Sorry but I am missing something.
>>
>> It was said in this thread (don't remember who, apologies) that
>>
>> YYYYMMDD
>>
>> would work.  Will it?
>
> Yes. YYYYMMDD is currently a valid version string (assuming it's all
> digits). Whatever we choose will allow a superset of what's already
> allowed.
>
> -Eric

That's true, but possibly stating the obvious: ASDF does not
"understand" a version string like that.  So you can't say "any version
since October 2020 will work." Getting something like that to work would
be an exercise for the extension protocol.

This actually might make a good test case for us to see if the proposed
protocol (versioning method keyword initarg for defsystem) makes sense.

R